貼個模板，以前學的EK算法算起來年紀比我還大一倍了，該換個模板了。
還有剛才CSDN肯定BUG了。。。。。
[cpp]
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <string>
#include <cmath>
#include <cstring>
#include <queue>
#include <set>
#include <vector>
#include <stack>
#include <map>
#include <iomanip>
#define PI acos(-1.0)
#define Max 2505
#define inf 1<<28
#define LL(x) (x<<1)
#define RR(x) (x<<1|1)
#define Rep(i,s,t) for(int i=(s);i<=(t);++i)
#define ll long long
#define mem(a,b) memset(a,b,sizeof(a))
#define mp(a,b) make_pair(a,b)
using namespace std;
struct kdq
{
int s ,e ,l ,next ;
}ed[Max * 100] ;
int head[Max] ,deep[Max] ,num ;
int qe[Max * 100] ;
void add(int s, int e ,int l )
{
ed[num].s = s ;
ed[num].e = e ;
ed[num].l = l ;
ed[num].next = head[s] ;
head[s] = num ++ ;
ed[num].s = e ;
ed[num].e = s ;
ed[num].l = 0 ;
ed[num].next =head[e] ;
head[e] = num ++ ;
}
void init()
{
mem(head,-1) ;
num = 0 ;
}
int S,T ;
int dinic_bfs()//bfs出每個點的深度
{
mem(deep,-1) ;
deep[S] = 0 ;
int h = 0 , t = 0 ;
qe[h ++] = S;
while(h > t)
{
int tt = qe[t ++] ;
for (int i = head[tt] ; ~i ;i = ed[i].next )
{
int e = ed[i].e ;
int l = ed[i].l ;
if(deep[e] == -1 && l > 0)
{
deep[e] = deep[tt] + 1 ;
qe[h ++] = e ;
}
}
}
return deep[T] != -1 ;
}
int dinic_dfs(int now ,int f)
{
if(now == T)
return f ;
int flow = 0 ;
for (int i = head[now] ; ~i ;i = ed[i].next )
{
int e = ed[i].e ;
int l = ed[i].l ;
if(deep[now] + 1 == deep[e] && l > 0)
{
int mm = min(l,f - flow) ;
int nn = dinic_dfs(e,mm) ;
flow += nn ;
ed[i].l -= nn ;
ed[i ^ 1].l += nn ;
}
}
if(!flow)//該點不需要再遍歷
deep[now] = -2 ;
return flow ;
}
int dinic()
{
int flow = 0 ;
int f = 0 ;
while(dinic_bfs())
{
while(f = dinic_dfs(S,inf))
{
flow += f ;
}
}
return flow ;
}
int mx[4] = {0,0,1,-1} ;
int my[4] = {1,-1,0,0} ;
int inmap(int x ,int y ,int n ,int m)
{
if(x > 0 && x <= n && y > 0 &&y <= m )return 1 ;return 0 ;
}
int main()
{
int n , m ;
while(cin >> n >> m )
{
int sum = 0 ;
init() ;
S = 0 ,T = n * m + 1 ;
for (int i = 1 ; i <= n ; i ++ )
{
for (int j = 1 ;j <= m ;j ++ )
{
int d ;
scanf("%d",&d) ;
sum += d ;
if((i + j) & 1)
{
add((i - 1) * m + j , T ,d) ;
for (int k = 0 ;k < 4 ;k ++ )
{
int tx = i + mx[k] ;
int ty = j + my[k] ;
if(inmap(tx,ty,n,m))
add((tx - 1 ) * m + ty , (i - 1 ) * m + j , inf) ;
}
}
else
{
add(S,(i - 1 ) * m + j , d ) ;
for (int k = 0 ;k < 4 ;k ++ )
{
int tx = i + mx[k] ;
int ty = j + my[k] ;
if(inmap(tx,ty,n,m))
add((i - 1 ) * m + j , ( tx - 1 ) * m + ty , inf) ;
}
}
}
}
cout <<sum - dinic() <<endl;
}
return 0 ;
}
